That tobacco use must be reduced to prevent cancer and many other chronic diseases is no longer in doubt. Equally certain is that to prevent tobacco use efforts must focus on adolescents. Tobacco use is adopted almost uniformly before the age of 20, and the average age of starting to smoke is about 13. Current tobacco use prevention programs have shown limited effectiveness with teenagers. The 1980s have seen virtually no decline in smoking rates among high school seniors, despite a decline in smoking rates among most other segments of our society, and a decline in illicit drug use among adolescents. While school based tobacco use prevention programs show limited effectiveness, in isolation they apparently do not have a broad or long-lasting enough effect to alter the prevalence of tobacco use by teenagers. Local policies which regulate the availability of tobacco to teenagers offer a promising complementary approach to reducing the prevalence of adolescent tobacco use. Many such policies are already in effect in some states and cities, and many more options are available for adoption. However existing policies are rarely enforced and virtually unevaluated, and so almost no information is available about the potential effectiveness of this approach. This proposal describes a randomized community trial of local policy changes to reduce tobacco availability in several upper midwestern cities. We propose to use a community organization intervention over a 2 year period to induce local policy change in such areas as enforcement of the age of sale law, the manner in which cigarettes are sold, and licensing ordinances. Tobacco use among teenagers will be assessed via community school surveys, and tobacco availability to teenagers will be measured by self report and by use of teenage confederates who will make systematic purchase attempts. This study will evaluate the effect of policy change on the ability of teenagers to purchase cigarettes and on the source of their cigarettes. Most importantly, this study will provide information about the effect of local policy changes on teenage smoking incidence and prevalence.